P0300 - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

2SSRS@Gen5diy · 11-28-2018, 09:26 AM

2 weeks ago our 2010 camaro LS3 started running bad all we got was a P0300 and when we started to work on it too find out what was not working, car seemed to be running on only 4 cylinders any one know whats going on?

Tested compression on all 8 and 7 had 160-165 PSI , 1 was 0, we had both fuel and spark to all 8 cylinders.

Hippy · 11-28-2018, 10:16 AM

Start with checking
For a Bad valve, Rocker broke..
Broken / stuck rings
Blown head gasket..

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camguynj · 11-28-2018, 10:26 AM

How many miles? Any engine mods ...how many miles go ?

2SSRS@Gen5diy · 11-28-2018, 12:29 PM

Quote:

Originally Posted by Hippy

Start with checking
For a Bad valve, Rocker broke..
Broken / stuck rings
Blown head gasket..

Sent from my SM-G955U using Tapatalk

Its non of that, we checked and like i said its only running on only 4 cylinders at the moment.

Quote:

Originally Posted by camguynj

How many miles? Any engine mods ...how many miles go ?

57K no mods this started a week ago and car has not moved, so may be 1-2 mi ago.

camguynj · 11-28-2018, 01:38 PM

Quote:

Originally Posted by 2SSRS@Gen5diy

Its non of that, we checked and like i said its only running on only 4 cylinders at the moment.

57K no mods this started a week ago and car has not moved, so may be 1-2 mi ago.

What did you do to check the valves, etc?

2SSRS@Gen5diy · 11-28-2018, 03:42 PM

Quote:

Originally Posted by camguynj

What did you do to check the valves, etc?

Well we did not pull the heads, but looked at them the valves are fine, but we did find a broken out side spring.

but how will that make it run on only 4 cylinders?.

hunter1660 · 11-28-2018, 04:17 PM

Dead cylinders all on same bank?...rat chewed thru harness wire? Wires make contact with exhaust and burn?

sixty9fordkiller · 11-28-2018, 04:37 PM

someone had this issue last week and itr ended up being fuelinjection related....ill look for the post

RankSS · 11-28-2018, 05:26 PM

Are you saying one of the cylinders has zero
compression???

xc_SS/RS · 11-28-2018, 09:19 PM

Check the coil and injector grounds on that side. My shop removed a spark plug that was stuck in the head and had one bank not fire at all after putting it back together. Turned out a ground wire had gotten cut

2SSRS@Gen5diy · 11-29-2018, 11:19 AM

Quote:

Originally Posted by hunter1660

Dead cylinders all on same bank?...rat chewed thru harness wire? Wires make contact with exhaust and burn?

No, 2 rears on both banks are not working, and wires are fine.

Quote:

Originally Posted by sixty9fordkiller

someone had this issue last week and itr ended up being fuelinjection related....ill look for the post

Thanks but all 8 are tested and work.

Quote:

Originally Posted by RankSS

Are you saying one of the cylinders has zero
compression???

Yes thats what we are saying.

Quote:

Originally Posted by xc_SS/RS

Check the coil and injector grounds on that side. My shop removed a spark plug that was stuck in the head and had one bank not fire at all after putting it back together. Turned out a ground wire had gotten cut

Its both sides, that only the rear 2 per side do not fire.

zlathim · 11-29-2018, 12:01 PM

Id start by figuring out why there is zero compression in the one cylinder. Sounds like there is a broken valve spring, so I would fix that, retest compression and then go from there. I'm curious how you know it is only running on 4 cylinders.

Hippy · 11-30-2018, 01:27 PM

Quote:

Originally Posted by 2SSRS@Gen5diy

2 weeks ago our 2010 camaro LS3 started running bad all we got was a P0300 and when we started to work on it too find out what was not working, car seemed to be running on only 4 cylinders any one know whats going on?

Tested compression on all 8 and 7 had 160-165 PSI , 1 was 0, we had both fuel and spark to all 8 cylinders.

Quote:

Originally Posted by 2SSRS@Gen5diy

2 weeks ago our 2010 camaro LS3 started running bad all we got was a P0300 and when we started to work on it too find out what was not working, car seemed to be running on only 4 cylinders any one know whats going on?

Tested compression on all 8 and 7 had 160-165 PSI , 1 was 0, we had both fuel and spark to all 8 cylinders.

Here you said 1 cylinder has 0 compression..

Doesn't matter if it has spark or not..In half or all of them. First figure out why there isn't compression.. In 1 cylinder

Have you tested for spark?
All I remember was that you said it seamed like it was only running on 4 cylinders

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2SSRS@Gen5diy · 12-05-2018, 01:09 PM

Quote:

Originally Posted by Hippy

Here you said 1 cylinder has 0 compression..

Yes it had 0 compression in #7 cylinder till we fixed it last night.

Doesn't matter if it has spark or not..In half or all of them. First figure out why there isn't compression.. In 1 cylinder

we know why cylinder #7 had a broken outer spring.

Have you tested for spark?

Yes all 8 had spark, that was tested, all 8 had fuel and the injectors where pulsing when tested.

All I remember was that you said it seamed like it was only running on 4 cylinders

We ran a infrared heat gun on all 8 cylinders, #1 and 3 and 2 and 4 where over 500+ degrees 5+7+6+8 where running 160 or so.

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So after we replace only one set of valve springs on #7 cylinder we tested the compression there all back to 165 LB and car starts and runs fine, its ward to me and my guys that only one cylinder made the rest of the rear cylinders run cooled and no power.

Last it did not trow a code for only one cylinder but the random P0300, any one know why?

11-28-2018, 10:16 AM	#2
Hippy Hotwheels Drives: Hotwheels Edition Join Date: Oct 2014 Location: New Jersey Posts: 382 View My Garage	Start with checking For a Bad valve, Rocker broke.. Broken / stuck rings Blown head gasket.. Sent from my SM-G955U using Tapatalk __________________ Parts for Sale 2013 2SS Hot Wheels Edition 734 of 1524

11-28-2018, 04:37 PM	#8
sixty9fordkiller Donkey Dick Cam Camaro Drives: 2010 2SS/RS LS3 M6 Join Date: Oct 2009 Location: Los Angeles, CA Posts: 1,998	someone had this issue last week and itr ended up being fuelinjection related....ill look for the post __________________ Bone Stock

11-28-2018, 05:26 PM	#9
RankSS Drives: 2010 Camaro SS Join Date: Oct 2013 Location: Saskatoon SK Can. Eh Posts: 365	Are you saying one of the cylinders has zero compression??? __________________ 2010 Camaro SS RS, Maggie with 3.4" pulley, 60# injectors, ADM dual fuel pumps, ADM Stage 2 Cam with Brian Tooley springs and pushrods, black CAI intake, Stainless Works long tube headers w/gutted cats, ZL1 Diff w/offset bushings, Pfadt lowering springs, Pfadt sway bars, Pfadt solid sub frame mounts, BMR trailing arms and toe rods, Hurst short throw shifter, Painted on Hugger Orange stripes, Forgestar F14 Piano Black wheels, Nitto NT05 rubber.

11-28-2018, 09:19 PM	#10
xc_SS/RS Drives: 2010 Camaro SS/RS Join Date: Mar 2014 Location: somewhere in MD Posts: 4,883	Check the coil and injector grounds on that side. My shop removed a spark plug that was stuck in the head and had one bank not fire at all after putting it back together. Turned out a ground wire had gotten cut __________________ 2010 2SS/RS Z/28 intake, NW, FAST 102, speed engineering LT's, some exhaust, ATI -10% pulley, GM flex fuel injectors, DSX flex fuel sensor, MGW shifter, HP Tuners, some suspension work, stickers and a little weight loss. 12.63 @113.53

11-29-2018, 12:01 PM	#12
zlathim Drives: 2010 Camaro 2SS/RS M6 Join Date: May 2009 Location: Idaho Posts: 726	Id start by figuring out why there is zero compression in the one cylinder. Sounds like there is a broken valve spring, so I would fix that, retest compression and then go from there. I'm curious how you know it is only running on 4 cylinders. __________________ GPI SS2; EE E2 catch can; SP 1 7/8" LT Headers w/ hfc; FM AT 3" cat-back; CAI Cold Air Intake; AEM Wideband Tuned by GPI McCleod RXT; MGW flat stick; Ram Clutch slave cylinder & hydraulic adjuster BMR cradle & diff bushings, trailing arms, toe rods & upper control arm bushings Hotchkis sub-frame brace Stop Tech Z-23 brakes 4.10 gears, Eaton Truetrac, LPW diff cover Best 1/4 mile 12.073 @ 115.68 mph 3,300 ft DA

11-28-2018, 09:26 AM	#1
2SSRS@Gen5diy Drives: 2014 Z/28 #82+#192, 18ZLE 66Nova Join Date: Oct 2008 Location: By the lake in AZ Posts: 15,719 View My Garage	P0300 2 weeks ago our 2010 camaro LS3 started running bad all we got was a P0300 and when we started to work on it too find out what was not working, car seemed to be running on only 4 cylinders any one know whats going on? Tested compression on all 8 and 7 had 160-165 PSI , 1 was 0, we had both fuel and spark to all 8 cylinders.

11-28-2018, 10:26 AM	#3
camguynj Drives: '13 SS/RS LS3 BRM Cammed NPP Join Date: Jan 2013 Location: NJ Posts: 3,812 View My Garage	How many miles? Any engine mods ...how many miles go ?

11-28-2018, 04:17 PM	#7
hunter1660 Drives: 2011ss/rs camaro Join Date: Sep 2011 Location: florida Posts: 1,261	Dead cylinders all on same bank?...rat chewed thru harness wire? Wires make contact with exhaust and burn? __________________ . OBX LTH,Rotofab,Magnuson Heartbeat.AEM wideband, HP Tuners